U.S. patent number 4,363,364 [Application Number 06/269,406] was granted by the patent office on 1982-12-14 for plow chisel with pointed shank having pointed chisel cap secured thereto by weld.
This patent grant is currently assigned to Adams Hard-Facing Company, Inc.. Invention is credited to Halsey J. Wetmore.
United States Patent |
4,363,364 |
Wetmore |
December 14, 1982 |
Plow chisel with pointed shank having pointed chisel cap secured
thereto by weld
Abstract
A plow chisel having an integrated chisel point and including an
elongated, arcuate shank portion formed as a curved, flat metal
plate having a top surface, bottom surface and two opposed side
edges. At one end, the shank portion is pointed due to convergence
of the side edges. A chisel cap of pointed configuration includes a
base relieved to receive the pointed end of the shank portion in a
recess of complementary shape. The cap is of hard metal
construction and is secured to the shank portion by welding.
Inventors: |
Wetmore; Halsey J. (Guymon,
OK) |
Assignee: |
Adams Hard-Facing Company, Inc.
(Guymon, OK)
|
Family
ID: |
23027110 |
Appl.
No.: |
06/269,406 |
Filed: |
May 29, 1981 |
Current U.S.
Class: |
172/732; 172/745;
172/747; 172/772; 76/DIG.4 |
Current CPC
Class: |
A01B
15/04 (20130101); A01B 35/20 (20130101); Y10S
76/04 (20130101) |
Current International
Class: |
A01B
15/00 (20060101); A01B 15/04 (20060101); A01B
35/00 (20060101); A01B 35/20 (20060101); A01B
015/02 () |
Field of
Search: |
;172/708,719,721,732,745,747,753,749,772 ;76/DIG.4,DIG.11 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Stouffer; Richard T.
Attorney, Agent or Firm: Laney; William R.
Claims
What is claimed is:
1. A plow chisel comprising:
an elongated arcuate shank portion having opposed parallel side
edges and having a point at one end thereof formed by the
convergence of said side edges;
a pointed chisel cap including a relieved base portion defining a
recess complementary in configuration to, and receiving, the point
of said shank portion, said chisel cap further including:
a pointed tip on the opposite end thereof from said base
portion;
an upper surface;
a lower surface which extends substantially parallel to the upper
surface and having a relief therein forming the recess in the base
portion, said relief having a configuration complementary to the
configuration of the point of said shank portion and having a
depth, as measured from said lower surface toward the upper
surface, which is less than the thickness of said shank portion
whereby said shank portion projects to a location below said lower
surface;
a pair of opposed, substantially parallel rear side surfaces
disposed on opposite sides of the recess and extending between the
upper surface and the lower surface;
a pair of convergent forward side surfaces each extending normal to
the lower surface and projecting upwardly therefrom and extending
from the rear side surfaces to the tip; and
a pair of convergent beveled surfaces projecting upwardly from the
forward side surfaces to the upper surface and inclined toward each
other and meeting in a line of convergence at an upper forward edge
inclined at an acute angle to said lower surface; and
weld metal in the angular corner space defined between said shank
portion and the lower surface of said chisel cap for securing said
chisel cap to said shank portion.
2. A plow chisel as defined in claim 1, wherein said cap is
constructed of chromium carbide.
3. A plow chisel as defined in claim 1 wherein a portion of said
chisel cap, including said upper surface, extends above said chisel
cap recess.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to agricultural implements, and more
particularly to a plow chisel.
2. Brief Description of the Prior Art
A number of types of chisel plows have been heretofore devised
which are intended to penetrate deeply into the earth so as to
break up the hardpan layer in the earth and permit moisture
penetration. Such chisel plows generally have an elongated curved
shank portion and a sharp point at the lower end of this shank
portion which is adapted to penetrate deeply into the earth and
break through the hardpan layer.
In the types of chisel plows heretofore known, abrasion and wear of
the points of the chisels has presented a problem of shortened
service life in such devices, requiring replacement or hard facing
after a relatively short period of hard usage.
Examples of types of plowing devices heretofore in use as such have
been known, and are believed to be closest in concept to the
present invention are the chisels manufactured by Adams Hard-Facing
Company of Guymon, Okla. and illustrated in the Adams 1979 Catalog
(copy sumbitted separately), the subsoil attachment for plows shown
in U.S. Pat. No. 680,400, the chisel shank and caps shown in
British Patent Specification No. 785,825, the hollow tip for a
cultivator tine shown in Lenke U.S. Pat. No. 3,439,636, and the
soil injector spear point disclosed in Hannibal U.S. Pat. No.
2,598,121.
BRIEF DESCRIPTION OF THE PRESENT INVENTION
The present invention provides an improved plow chisel of generally
two-part construction, including an elongated arcuate shank and a
chisel point or cap placed on one end of this shank. The elongated
arcuate shank is formed as a curved, flat metal plate having a top
surface, a bottom surface, and two opposed side edges. At one end
the shank portion is pointed due to a convergence of the side
edges. The chisel cap is also of pointed configuration and includes
a base which is relieved to receive the pointed end of the shank
portion in a recess which is of complementary shape to the pointed
end of the shank portion. The cap is of hard metal construction,
such as chromium carbide, and is welded to the shank portion after
interfitting of the cap on the shank portion.
An important feature of the present invention is the ease with
which a very hard point or cap may be placed on the lower end of a
plow chisel so as to impart extended service life and enhanced
abrasion resistance to this plow chisel.
Another important object of the invention is to provide a compact,
easily used and constructed plow chisel which is mechanically
durable and can be easily mounted and used by the farmer.
Additional objects and advantages of the invention will become
apparent as the following detailed description is read in
conjunction with the accompanying drawings which illustrate a
preferred embodiment of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a side elevation view of a plow chisel constructed in
accordance with the present invention.
FIG. 2 is a front elevation view of the plow chisel shown in FIG.
1.
FIG. 3 is a perspective view of the shank portion of the plow
chisel of the invention.
FIG. 4 is a side elevation view of the chisel cap, forming a part
of the plow chisel of the invention.
FIG. 5 is a bottom plan view of the chisel cap shown in FIG. 4.
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION
Referring initially to FIG. 1 in the drawings, the plow chisel of
the invention includes an elongated, arcuate shank portion
designated generally by reference numeral 10 and a chisel cap or
point, designated generally by reference numeral 12. The shank
portion is a curved metal plate having an upper surface 14. A lower
surface (not visible) and two opposed, substantially parallel side
edges 16 and 18. Intermediate its length, a pair of bolt apertures
20 and 22 are provided through the shank portion to enable the
shank portion to be affixed to a supporting structure on a plow
frame. At its lower end, the shank portion is pointed with the
point thereon being formed by convergance of the side edges 16 and
18 as illustrated at 16a and 18a.
The chisel cap 12 is preferably constructed of a very hard
material, such as chromium carbide, and includes a tip or point 24,
a base portion at the opposite side thereof from the tip, an upper
surface 26 and a lower surface 28 which extends substantially
parallel to the upper surface. The cap further includes a pair of
opposed, substantially parallel rear side surfaces 30 and 32, and a
pair of reduced width, forward side surfaces 34 and 36. A pair of
beveled or inclined surfaces 38 and 40 are provided along the
forward portion of the chisel cap 12 and project upwardly from the
forward side surfaces 34 and 36. The beveled surfaces 38 and 40
converge at an inclined upper, forward edge 42 which slopes
downwardly to the point 24.
The lower surface 28 of the chisel cap 12 is relieved at the base
portion in the manner shown in FIG. 5. The relief in the chisel cap
is basically configured so as to accommodate the pointed lower end
of the shank portion 10 defined by the convergence of the side
edges 16 and 18. The relief in the lower surface 28 of the chisel
cap 12 is substantially complementary in configuration to the
pointed lower end of the shank portion 10, thus being generally
triangular in configuration and having a pair of convergent sides
44 and 46. The relief is cut to a depth in the chisel cap, as
measured from the lower surface 28 toward the upper surface 26
thereof, which is slightly less than the thickness of the shank
portion 10, and this relationship is illustrated in FIG. 1 of the
drawings.
In the construction of the plow chisel of the invention, the chisel
cap 12 is fitted upon the lower end of the shank portion 10 and is
welded in that location by means of a weld metal having a high
degree of hardness and abrasion resistance. The interfitting of the
configuration of the lower end of the shank portion 10 with the
relief formed in the chisel cap 12 assures a strong solid
connection when the welding is completed.
The plow chisel of the invention is characterized in having a long
or extended and trouble-free service life. While the chisel cap is
very abrasion-resistant and retains its penetrating and cutting
function for a long period of time, it can be easily replaced if it
should be lost from the lower end of the shank portion. The entire
plow chisel is quickly and easily attached to a supporting member
carried on a plow frame, and can be detached and replaced
easily.
Although a preferred embodiment of the invention has been
illustrated herein, in order to provide an understanding and
comprehension of the basic principles which underlie the invention,
it will be understood that various changes and modifications can be
effected in the illustrated embodiment without departure from such
basic principles. Changes and innovations of that type are
therefore deemed to be circumscribed by the spirit and scope of the
invention as defined by the appended claims or reasonable
equivalence thereof.
* * * * *